The paper presents a method for synchronous generator parameter estimation using real time operating data. Developed parameter estimation algorithm is applied in a design of the excitation system. Input data for model analysis is acquired from fault recorder and SCADA systems.
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This paper attempts to investigate the approach of linear quadratic Gaussian methodology with loop transfer recovery (LQG/LTR) for hydro turbine control. The Kalman filter estimates the state of the plant and an optimal control law is used to minimize the performance index represented as quadratic objective function. First the model is simulated with LQR (Linear Quadratic Regulator) considering th...
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The tests carried out in electrical and electronic laboratories allow researchers to advance in the field of superposing voltages techniques. The use of simulation software applications are mentioned as part of this study. The real measurements have been taken in two environments. The first tests were developed over the line used to feed the laboratory equipment. The second activity has been carri...
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The extended testing of hydrogenerator (rated 35 MVA) was made because the generators working age expired and it was going to be replaced with new one. This was the perfect opportunity to do some specific and not usual testing. The complicated testing plan was designed in order to enable recording as much relevant data as possible (electrical, electromechanical, mechanical). Therefore in some phas...
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Space-time block (STB) coding is one of the key techniques used to combat fading in multiantenna wireless communication systems. STB coding provides diversity gain while having a simple decoding. However, when further gains are needed, an outer channel code has to be concatenated. Turbo codes are channel codes that have been shown to perform close to the Shannon limits in AWGN channels. Moreover, ...
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Slovenia is 10-times poorer with conventional energy sources than other countries of the world. Only exploitation of coal in the regions of Velenje and Zasavje is economically justifiable. Unfortunately, coal in these two regions is environmentally problematic, and reserves are sufficient only for about 40 years of exploitation. Reserves of uranium are bigger, but their exploitation is environment...
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A simple measurement is proposed for source identification and characterization. Power transformer is proposed as a point to perform the measurements in a cheap and practical way. Simulation has been undertaken to confirm validity of the proposed method. The procedure for the load characterization, outlined in this paper, has been tested in real power distribution system to establish the contribut...
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Electric drive is increasingly gaining in importance within the general ship propulsion system. Contemporary electric propulsion mainly contains a fixed propeller, a synchronous or asynchronous propulsion engine and a PWM frequency converter with an adequate drive. During recent years the azimuth system has become the most popular concept within the shipboard electric propulsion system. Ship's man...
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Eigenvalues of a power system can explain the system stability in its operating point. In this paper the linear analysis capabilities of two software packages are evaluated and compared. The paper also illustrates the impact of the models of the power system components (like generators) on the location of the eigenvalues. Eigenvalue analysis are not only dependent on the properties of the investig...
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This paper addresses the market for reserve capacity that was introduced in Norway in 2000 as a consequence of a narrowing capacity margin. The new element introduced by this market is a market-based payment for availability. A simulation model is developed to show how this market interacts with the spot and regulating markets and leads to an equilibrium. We study how changed spot demand and chang...
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Transient heat transfer analysis of medium voltage, PE and XLPE insulated underground power cables are investigated by applying finite element modeling developed under a finite element software utilizing principle of virtual temperatures which is the quadratic functional form of the variational formulation of the transient heat transfer equation. Obtained results are compared with and verified by ...
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In this paper, the dynamic performance of a small-hydro induction generation system integrated into grid is studied. The mathematical models including hydraulic turbine prime mover model, induction generator model, electromechanical model, power factor correction capacitor bank model are employed to cater for the dynamic behavior of the system operating under load importing, exporting, sequentiall...
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This paper addresses the problem of wind profile and wind turbine power estimation. A complex-valued pipelined recurrent neural network (CPRNN) architecture is proposed. The network is trained by the complex-valued real-time recurrent learning (CRTRL) algorithm with a general 'fully' complex activation function which makes it suitable for forecasting wind signal in its complex form (speed and dire...
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In this paper, an efficient power system modeling technique by utilizing the concept of multiterminal component is introduced. The proposed technique is based on gathering the same phase busses and elements as a separate group (phase grouping technique) and uses multiterminal components to model a three-phase power system. Using a multiterminal component and phase grouping technique (PGT), power s...
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The paper analyses the dynamics of generator-units during start-up of the induction motor drives. A unique mathematical model of integral motor drives has been developed, consisting of: a diesel engine, a synchronous generator and two nonregulated motor drives fed directly from generator-unit terminals. The aim of this paper is to compare dynamics behaviors of the generator-units during starting t...
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The selection and the valuation of a power project reveal a very difficult task in a liberalized electricity market. In conjunction with the highly capital-intensive feature of electricity supply, different factors can influence the profitability of the investment, such as: market rules, plant location, load demand and fuel cost trend, etc. In this paper, a methodology based on the long-term simul...
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In this paper a methodology that handles a wide range of flow limits by extension and formulation of a continuation power flow so that include generator redispatch when a flow on a given line exceeds some specified limit, is proposed. Four options for active generation redispatch are introduced: based on topology analysis, sensitivity studies, generator margins, and cost considerations. The applic...
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The common cases of a nonselective operation of the phase to ground fault protection in the insulated power grids, which utilize inductive sensors for a voltage unbalance indication, are explained by ferroresonant processes in voltage transformers of healthy drains. This paper deals with phase to ground faults simulations in a known grid, that provide information about possible nonselective phase ...
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In this work we present a locally developed integrated optics technology for the fabrication and characterization of integrated optical components. The fabrication was carried out using the ion exchange in glass. Both single mode guides and multi-mode interference MMI splitter are, for the first time in Egypt, fabricated and tested. For the characterization purpose, an automated setup is developed...
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This paper reports on the results of a study carried out on the basis of information obtained from real case investigations on residential customer behaviour, lifestyle, and usage of the appliances. The aggregated load patterns of single-house customers have been first computed by using a bottom-up approach. Then, the time-dependent uncertainty of the aggregated load power has been assessed from s...
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This paper presents a new definition of the market share for reactive market power assessment. The proposed definition takes into account the order with which the generators reach their reactive power limits when the load varies along a predefined direction. The reactive market power is then defined on the basis of the market share. Results of tests carried out on the IEEE 57-bus test system are p...
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Renewable generation systems are increasing its presence in electrical power systems. For this reason, it is more important than ever to count with reliable and secure generation systems. In this way, the use of on-line diagnostic techniques in the maintenance schemes can be useful. This paper is about on-line condition monitoring in induction generators for small hydro stations and wind farms. In...
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Simulation programs have become a very interesting tool in education. The department of electronics and telecommunications, taking notice of the great advances in computers has developed an application for making students easier acquisition of basic knowledges about transformation centres. This educational tool has been made to teach the students, both, how Matlab works, and how to simulate a tran...
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The effect that the instantaneous compensation in three-phase four-wire systems, including or not the compensation of the neutral current, has on the supply-line power losses is studied in this paper. According to the instantaneous value concept, the noninstantaneous-active current can be reduced without altering the instantaneous active power. Two approaches are considered in this paper for insta...
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This paper addresses the optimization of voltage control in distribution systems in the presence of distributed generation. The objective is minimizing the voltage deviations at the load nodes with respect to specified reference values. The optimization is solved by means of a new approach based on nested evolutionary programming. Results are shown on a test system including controls at the HV/MV ...
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